Two Colorado cantaloupe farmers will not go to prison but were sentenced Tuesday to probation and home detention for their role in a listeria outbreak that killed 33 people in 2011. The Food and Drug Administration called it the deadliest foodborne illness outbreak in the USA since 1924

Eric and Ryan Jensen, the two brothers who owned and operated Jensen Farms in Holly, Colo., were sentenced in federal court in Denver.

Each received five years probation and six months home detention. Each also was ordered to pay $150,000 in restitution and perform 100 hours of community service.

The Jensens apologized for the listeria outbreak, which was traced to their farm. They had asked for probation, saying justice has been served because federal regulations have been put in place that will reduce the likelihood of a repeat tragedy.

Magistrate Judge Michael E. Hegarty said he did not order prison time or fines so the brothers could keep working to support their families and pay restitution.

"I must deliver both justice and mercy at the same time," Hegarty said.

Federal prosecutors also had asked for probation. Relatives of seven victims took the stand before sentencing, some saying the men should not go to prison and others asking for prison time.

The Jensens pleaded guilty last year to misdemeanor counts of introducing adulterated food into interstate commerce, which carry penalties of up to six years in prison and $1.5 million in fines. They pleaded not guilty to criminal charges.

Their attorneys argued in court filings that the case "has already prompted a new awareness of food safety law and the strict liability imposed on producers and food processors. Any desired respect for the law has been accomplished."

Months before the outbreak, President Obama signed into law a food safety bill designed to shift the focus of federal regulators from responding to contamination to preventing it. The U.S. Food and Drug Administration called the Colorado outbreak "the latest illustration of the continuing need for a strong food-safety program."

Its investigation found multiple problems, including evidence that the melons likely were contaminated in the farm's packing house because of dirty water on the floor and old, hard-to-clean equipment.

The FDA also has said that the rare move to charge the Jensens was intended to send a message to food producers.

The Centers for Disease Control and Prevention linked cantaloupe grown at Jensen Farms to the listeria outbreak that began at the end of August 2011. In October 2011, the FDA found that Jensen Farms' packing and storage facilities likely helped spread the listeria and directly contributed to the outbreak.

More than 125 people in 28 states fell ill from cantaloupe linked to the Colorado farm, the CDC said.

Listeriosis from listeria bacteria is a serious infection that primarily affects older adults, pregnant women, newborns and adults with weakened immune systems. Fever and muscle aches sometimes accompany diarrhea or other digestive problems. Pregnant women face a risk of miscarriage, which one survivor experienced. Convulsions also are possible in severe cases, according to the CDC.

The more bacteria in the food eaten, the more quickly the person becomes ill. "With listeria, it's growing within the person until it reaches some threshold and spills over. From there it migrates from the gut to the liver and then the blood and the central nervous system," said Ben Silk, an epidemiologist at CDC who led the listeria investigation.